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v6.8
  1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
  2/*
  3 * Copyright (C) 2005-2014, 2018-2019, 2021 Intel Corporation
  4 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  5#include <linux/types.h>
  6#include <linux/slab.h>
  7#include <linux/export.h>
  8
  9#include "iwl-drv.h"
 10#include "iwl-debug.h"
 11#include "iwl-eeprom-read.h"
 12#include "iwl-io.h"
 13#include "iwl-prph.h"
 14#include "iwl-csr.h"
 15
 16/*
 17 * EEPROM access time values:
 18 *
 19 * Driver initiates EEPROM read by writing byte address << 1 to CSR_EEPROM_REG.
 20 * Driver then polls CSR_EEPROM_REG for CSR_EEPROM_REG_READ_VALID_MSK (0x1).
 21 * When polling, wait 10 uSec between polling loops, up to a maximum 5000 uSec.
 22 * Driver reads 16-bit value from bits 31-16 of CSR_EEPROM_REG.
 23 */
 24#define IWL_EEPROM_ACCESS_TIMEOUT	5000 /* uSec */
 25
 
 
 
 
 26/*
 27 * The device's EEPROM semaphore prevents conflicts between driver and uCode
 28 * when accessing the EEPROM; each access is a series of pulses to/from the
 29 * EEPROM chip, not a single event, so even reads could conflict if they
 30 * weren't arbitrated by the semaphore.
 31 */
 32#define IWL_EEPROM_SEM_TIMEOUT		10   /* microseconds */
 33#define IWL_EEPROM_SEM_RETRY_LIMIT	1000 /* number of attempts (not time) */
 34
 
 
 35
 36static int iwl_eeprom_acquire_semaphore(struct iwl_trans *trans)
 37{
 38	u16 count;
 39	int ret;
 40
 41	for (count = 0; count < IWL_EEPROM_SEM_RETRY_LIMIT; count++) {
 42		/* Request semaphore */
 43		iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
 44			    CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
 45
 46		/* See if we got it */
 47		ret = iwl_poll_bit(trans, CSR_HW_IF_CONFIG_REG,
 48				CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
 49				CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
 50				IWL_EEPROM_SEM_TIMEOUT);
 51		if (ret >= 0) {
 52			IWL_DEBUG_EEPROM(trans->dev,
 53					 "Acquired semaphore after %d tries.\n",
 54					 count+1);
 55			return ret;
 56		}
 57	}
 58
 59	return ret;
 60}
 61
 62static void iwl_eeprom_release_semaphore(struct iwl_trans *trans)
 63{
 64	iwl_clear_bit(trans, CSR_HW_IF_CONFIG_REG,
 65		      CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
 66}
 67
 68static int iwl_eeprom_verify_signature(struct iwl_trans *trans, bool nvm_is_otp)
 69{
 70	u32 gp = iwl_read32(trans, CSR_EEPROM_GP) & CSR_EEPROM_GP_VALID_MSK;
 71
 72	IWL_DEBUG_EEPROM(trans->dev, "EEPROM signature=0x%08x\n", gp);
 73
 74	switch (gp) {
 75	case CSR_EEPROM_GP_BAD_SIG_EEP_GOOD_SIG_OTP:
 76		if (!nvm_is_otp) {
 77			IWL_ERR(trans, "EEPROM with bad signature: 0x%08x\n",
 78				gp);
 79			return -ENOENT;
 80		}
 81		return 0;
 82	case CSR_EEPROM_GP_GOOD_SIG_EEP_LESS_THAN_4K:
 83	case CSR_EEPROM_GP_GOOD_SIG_EEP_MORE_THAN_4K:
 84		if (nvm_is_otp) {
 85			IWL_ERR(trans, "OTP with bad signature: 0x%08x\n", gp);
 86			return -ENOENT;
 87		}
 88		return 0;
 89	case CSR_EEPROM_GP_BAD_SIGNATURE_BOTH_EEP_AND_OTP:
 90	default:
 91		IWL_ERR(trans,
 92			"bad EEPROM/OTP signature, type=%s, EEPROM_GP=0x%08x\n",
 93			nvm_is_otp ? "OTP" : "EEPROM", gp);
 94		return -ENOENT;
 95	}
 96}
 97
 98/******************************************************************************
 99 *
100 * OTP related functions
101 *
102******************************************************************************/
103
104static void iwl_set_otp_access_absolute(struct iwl_trans *trans)
105{
106	iwl_read32(trans, CSR_OTP_GP_REG);
107
108	iwl_clear_bit(trans, CSR_OTP_GP_REG,
109		      CSR_OTP_GP_REG_OTP_ACCESS_MODE);
110}
111
112static int iwl_nvm_is_otp(struct iwl_trans *trans)
113{
114	u32 otpgp;
115
116	/* OTP only valid for CP/PP and after */
117	switch (trans->hw_rev & CSR_HW_REV_TYPE_MSK) {
118	case CSR_HW_REV_TYPE_NONE:
119		IWL_ERR(trans, "Unknown hardware type\n");
120		return -EIO;
121	case CSR_HW_REV_TYPE_5300:
122	case CSR_HW_REV_TYPE_5350:
123	case CSR_HW_REV_TYPE_5100:
124	case CSR_HW_REV_TYPE_5150:
125		return 0;
126	default:
127		otpgp = iwl_read32(trans, CSR_OTP_GP_REG);
128		if (otpgp & CSR_OTP_GP_REG_DEVICE_SELECT)
129			return 1;
130		return 0;
131	}
132}
133
134static int iwl_init_otp_access(struct iwl_trans *trans)
135{
136	int ret;
137
138	ret = iwl_finish_nic_init(trans);
139	if (ret)
140		return ret;
141
142	iwl_set_bits_prph(trans, APMG_PS_CTRL_REG,
143			  APMG_PS_CTRL_VAL_RESET_REQ);
144	udelay(5);
145	iwl_clear_bits_prph(trans, APMG_PS_CTRL_REG,
146			    APMG_PS_CTRL_VAL_RESET_REQ);
147
148	/*
149	 * CSR auto clock gate disable bit -
150	 * this is only applicable for HW with OTP shadow RAM
151	 */
152	if (trans->trans_cfg->base_params->shadow_ram_support)
153		iwl_set_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
154			    CSR_RESET_LINK_PWR_MGMT_DISABLED);
155
156	return 0;
 
 
 
 
 
 
 
 
 
157}
158
159static int iwl_read_otp_word(struct iwl_trans *trans, u16 addr,
160			     __le16 *eeprom_data)
161{
162	int ret = 0;
163	u32 r;
164	u32 otpgp;
165
166	iwl_write32(trans, CSR_EEPROM_REG,
167		    CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
168	ret = iwl_poll_bit(trans, CSR_EEPROM_REG,
169				 CSR_EEPROM_REG_READ_VALID_MSK,
170				 CSR_EEPROM_REG_READ_VALID_MSK,
171				 IWL_EEPROM_ACCESS_TIMEOUT);
172	if (ret < 0) {
173		IWL_ERR(trans, "Time out reading OTP[%d]\n", addr);
174		return ret;
175	}
176	r = iwl_read32(trans, CSR_EEPROM_REG);
177	/* check for ECC errors: */
178	otpgp = iwl_read32(trans, CSR_OTP_GP_REG);
179	if (otpgp & CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK) {
180		/* stop in this case */
181		/* set the uncorrectable OTP ECC bit for acknowledgment */
182		iwl_set_bit(trans, CSR_OTP_GP_REG,
183			    CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
184		IWL_ERR(trans, "Uncorrectable OTP ECC error, abort OTP read\n");
185		return -EINVAL;
186	}
187	if (otpgp & CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK) {
188		/* continue in this case */
189		/* set the correctable OTP ECC bit for acknowledgment */
190		iwl_set_bit(trans, CSR_OTP_GP_REG,
191			    CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK);
192		IWL_ERR(trans, "Correctable OTP ECC error, continue read\n");
193	}
194	*eeprom_data = cpu_to_le16(r >> 16);
195	return 0;
196}
197
198/*
199 * iwl_is_otp_empty: check for empty OTP
200 */
201static bool iwl_is_otp_empty(struct iwl_trans *trans)
202{
203	u16 next_link_addr = 0;
204	__le16 link_value;
205	bool is_empty = false;
206
207	/* locate the beginning of OTP link list */
208	if (!iwl_read_otp_word(trans, next_link_addr, &link_value)) {
209		if (!link_value) {
210			IWL_ERR(trans, "OTP is empty\n");
211			is_empty = true;
212		}
213	} else {
214		IWL_ERR(trans, "Unable to read first block of OTP list.\n");
215		is_empty = true;
216	}
217
218	return is_empty;
219}
220
221
222/*
223 * iwl_find_otp_image: find EEPROM image in OTP
224 *   finding the OTP block that contains the EEPROM image.
225 *   the last valid block on the link list (the block _before_ the last block)
226 *   is the block we should read and used to configure the device.
227 *   If all the available OTP blocks are full, the last block will be the block
228 *   we should read and used to configure the device.
229 *   only perform this operation if shadow RAM is disabled
230 */
231static int iwl_find_otp_image(struct iwl_trans *trans,
232					u16 *validblockaddr)
233{
234	u16 next_link_addr = 0, valid_addr;
235	__le16 link_value = 0;
236	int usedblocks = 0;
237
238	/* set addressing mode to absolute to traverse the link list */
239	iwl_set_otp_access_absolute(trans);
240
241	/* checking for empty OTP or error */
242	if (iwl_is_otp_empty(trans))
243		return -EINVAL;
244
245	/*
246	 * start traverse link list
247	 * until reach the max number of OTP blocks
248	 * different devices have different number of OTP blocks
249	 */
250	do {
251		/* save current valid block address
252		 * check for more block on the link list
253		 */
254		valid_addr = next_link_addr;
255		next_link_addr = le16_to_cpu(link_value) * sizeof(u16);
256		IWL_DEBUG_EEPROM(trans->dev, "OTP blocks %d addr 0x%x\n",
257				 usedblocks, next_link_addr);
258		if (iwl_read_otp_word(trans, next_link_addr, &link_value))
259			return -EINVAL;
260		if (!link_value) {
261			/*
262			 * reach the end of link list, return success and
263			 * set address point to the starting address
264			 * of the image
265			 */
266			*validblockaddr = valid_addr;
267			/* skip first 2 bytes (link list pointer) */
268			*validblockaddr += 2;
269			return 0;
270		}
271		/* more in the link list, continue */
272		usedblocks++;
273	} while (usedblocks <= trans->trans_cfg->base_params->max_ll_items);
274
275	/* OTP has no valid blocks */
276	IWL_DEBUG_EEPROM(trans->dev, "OTP has no valid blocks\n");
277	return -EINVAL;
278}
279
280/*
281 * iwl_read_eeprom - read EEPROM contents
282 *
283 * Load the EEPROM contents from adapter and return it
284 * and its size.
285 *
286 * NOTE:  This routine uses the non-debug IO access functions.
287 */
288int iwl_read_eeprom(struct iwl_trans *trans, u8 **eeprom, size_t *eeprom_size)
289{
290	__le16 *e;
291	u32 gp = iwl_read32(trans, CSR_EEPROM_GP);
292	int sz;
293	int ret;
294	u16 addr;
295	u16 validblockaddr = 0;
296	u16 cache_addr = 0;
297	int nvm_is_otp;
298
299	if (!eeprom || !eeprom_size)
300		return -EINVAL;
301
302	nvm_is_otp = iwl_nvm_is_otp(trans);
303	if (nvm_is_otp < 0)
304		return nvm_is_otp;
305
306	sz = trans->trans_cfg->base_params->eeprom_size;
307	IWL_DEBUG_EEPROM(trans->dev, "NVM size = %d\n", sz);
308
309	e = kmalloc(sz, GFP_KERNEL);
310	if (!e)
311		return -ENOMEM;
312
313	ret = iwl_eeprom_verify_signature(trans, nvm_is_otp);
314	if (ret < 0) {
315		IWL_ERR(trans, "EEPROM not found, EEPROM_GP=0x%08x\n", gp);
316		goto err_free;
317	}
318
319	/* Make sure driver (instead of uCode) is allowed to read EEPROM */
320	ret = iwl_eeprom_acquire_semaphore(trans);
321	if (ret < 0) {
322		IWL_ERR(trans, "Failed to acquire EEPROM semaphore.\n");
323		goto err_free;
324	}
325
326	if (nvm_is_otp) {
327		ret = iwl_init_otp_access(trans);
328		if (ret) {
329			IWL_ERR(trans, "Failed to initialize OTP access.\n");
330			goto err_unlock;
331		}
332
333		iwl_write32(trans, CSR_EEPROM_GP,
334			    iwl_read32(trans, CSR_EEPROM_GP) &
335			    ~CSR_EEPROM_GP_IF_OWNER_MSK);
336
337		iwl_set_bit(trans, CSR_OTP_GP_REG,
338			    CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK |
339			    CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
340		/* traversing the linked list if no shadow ram supported */
341		if (!trans->trans_cfg->base_params->shadow_ram_support) {
342			ret = iwl_find_otp_image(trans, &validblockaddr);
343			if (ret)
344				goto err_unlock;
345		}
346		for (addr = validblockaddr; addr < validblockaddr + sz;
347		     addr += sizeof(u16)) {
348			__le16 eeprom_data;
349
350			ret = iwl_read_otp_word(trans, addr, &eeprom_data);
351			if (ret)
352				goto err_unlock;
353			e[cache_addr / 2] = eeprom_data;
354			cache_addr += sizeof(u16);
355		}
356	} else {
357		/* eeprom is an array of 16bit values */
358		for (addr = 0; addr < sz; addr += sizeof(u16)) {
359			u32 r;
360
361			iwl_write32(trans, CSR_EEPROM_REG,
362				    CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
363
364			ret = iwl_poll_bit(trans, CSR_EEPROM_REG,
365					   CSR_EEPROM_REG_READ_VALID_MSK,
366					   CSR_EEPROM_REG_READ_VALID_MSK,
367					   IWL_EEPROM_ACCESS_TIMEOUT);
368			if (ret < 0) {
369				IWL_ERR(trans,
370					"Time out reading EEPROM[%d]\n", addr);
371				goto err_unlock;
372			}
373			r = iwl_read32(trans, CSR_EEPROM_REG);
374			e[addr / 2] = cpu_to_le16(r >> 16);
375		}
376	}
377
378	IWL_DEBUG_EEPROM(trans->dev, "NVM Type: %s\n",
379			 nvm_is_otp ? "OTP" : "EEPROM");
380
381	iwl_eeprom_release_semaphore(trans);
382
383	*eeprom_size = sz;
384	*eeprom = (u8 *)e;
385	return 0;
386
387 err_unlock:
388	iwl_eeprom_release_semaphore(trans);
389 err_free:
390	kfree(e);
391
392	return ret;
393}
394IWL_EXPORT_SYMBOL(iwl_read_eeprom);
v4.17
  1/******************************************************************************
  2 *
  3 * This file is provided under a dual BSD/GPLv2 license.  When using or
  4 * redistributing this file, you may do so under either license.
  5 *
  6 * GPL LICENSE SUMMARY
  7 *
  8 * Copyright(c) 2008 - 2014 Intel Corporation. All rights reserved.
  9 *
 10 * This program is free software; you can redistribute it and/or modify
 11 * it under the terms of version 2 of the GNU General Public License as
 12 * published by the Free Software Foundation.
 13 *
 14 * This program is distributed in the hope that it will be useful, but
 15 * WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 * General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, write to the Free Software
 21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
 22 * USA
 23 *
 24 * The full GNU General Public License is included in this distribution
 25 * in the file called COPYING.
 26 *
 27 * Contact Information:
 28 *  Intel Linux Wireless <linuxwifi@intel.com>
 29 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 30 *
 31 * BSD LICENSE
 32 *
 33 * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.
 34 * All rights reserved.
 35 *
 36 * Redistribution and use in source and binary forms, with or without
 37 * modification, are permitted provided that the following conditions
 38 * are met:
 39 *
 40 *  * Redistributions of source code must retain the above copyright
 41 *    notice, this list of conditions and the following disclaimer.
 42 *  * Redistributions in binary form must reproduce the above copyright
 43 *    notice, this list of conditions and the following disclaimer in
 44 *    the documentation and/or other materials provided with the
 45 *    distribution.
 46 *  * Neither the name Intel Corporation nor the names of its
 47 *    contributors may be used to endorse or promote products derived
 48 *    from this software without specific prior written permission.
 49 *
 50 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 51 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 52 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 53 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 54 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 55 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 56 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 57 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 58 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 59 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 60 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 61 *****************************************************************************/
 62#include <linux/types.h>
 63#include <linux/slab.h>
 64#include <linux/export.h>
 65
 66#include "iwl-drv.h"
 67#include "iwl-debug.h"
 68#include "iwl-eeprom-read.h"
 69#include "iwl-io.h"
 70#include "iwl-prph.h"
 71#include "iwl-csr.h"
 72
 73/*
 74 * EEPROM access time values:
 75 *
 76 * Driver initiates EEPROM read by writing byte address << 1 to CSR_EEPROM_REG.
 77 * Driver then polls CSR_EEPROM_REG for CSR_EEPROM_REG_READ_VALID_MSK (0x1).
 78 * When polling, wait 10 uSec between polling loops, up to a maximum 5000 uSec.
 79 * Driver reads 16-bit value from bits 31-16 of CSR_EEPROM_REG.
 80 */
 81#define IWL_EEPROM_ACCESS_TIMEOUT	5000 /* uSec */
 82
 83#define IWL_EEPROM_SEM_TIMEOUT		10   /* microseconds */
 84#define IWL_EEPROM_SEM_RETRY_LIMIT	1000 /* number of attempts (not time) */
 85
 86
 87/*
 88 * The device's EEPROM semaphore prevents conflicts between driver and uCode
 89 * when accessing the EEPROM; each access is a series of pulses to/from the
 90 * EEPROM chip, not a single event, so even reads could conflict if they
 91 * weren't arbitrated by the semaphore.
 92 */
 
 
 93
 94#define	EEPROM_SEM_TIMEOUT 10		/* milliseconds */
 95#define EEPROM_SEM_RETRY_LIMIT 1000	/* number of attempts (not time) */
 96
 97static int iwl_eeprom_acquire_semaphore(struct iwl_trans *trans)
 98{
 99	u16 count;
100	int ret;
101
102	for (count = 0; count < EEPROM_SEM_RETRY_LIMIT; count++) {
103		/* Request semaphore */
104		iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
105			    CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
106
107		/* See if we got it */
108		ret = iwl_poll_bit(trans, CSR_HW_IF_CONFIG_REG,
109				CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
110				CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM,
111				EEPROM_SEM_TIMEOUT);
112		if (ret >= 0) {
113			IWL_DEBUG_EEPROM(trans->dev,
114					 "Acquired semaphore after %d tries.\n",
115					 count+1);
116			return ret;
117		}
118	}
119
120	return ret;
121}
122
123static void iwl_eeprom_release_semaphore(struct iwl_trans *trans)
124{
125	iwl_clear_bit(trans, CSR_HW_IF_CONFIG_REG,
126		      CSR_HW_IF_CONFIG_REG_BIT_EEPROM_OWN_SEM);
127}
128
129static int iwl_eeprom_verify_signature(struct iwl_trans *trans, bool nvm_is_otp)
130{
131	u32 gp = iwl_read32(trans, CSR_EEPROM_GP) & CSR_EEPROM_GP_VALID_MSK;
132
133	IWL_DEBUG_EEPROM(trans->dev, "EEPROM signature=0x%08x\n", gp);
134
135	switch (gp) {
136	case CSR_EEPROM_GP_BAD_SIG_EEP_GOOD_SIG_OTP:
137		if (!nvm_is_otp) {
138			IWL_ERR(trans, "EEPROM with bad signature: 0x%08x\n",
139				gp);
140			return -ENOENT;
141		}
142		return 0;
143	case CSR_EEPROM_GP_GOOD_SIG_EEP_LESS_THAN_4K:
144	case CSR_EEPROM_GP_GOOD_SIG_EEP_MORE_THAN_4K:
145		if (nvm_is_otp) {
146			IWL_ERR(trans, "OTP with bad signature: 0x%08x\n", gp);
147			return -ENOENT;
148		}
149		return 0;
150	case CSR_EEPROM_GP_BAD_SIGNATURE_BOTH_EEP_AND_OTP:
151	default:
152		IWL_ERR(trans,
153			"bad EEPROM/OTP signature, type=%s, EEPROM_GP=0x%08x\n",
154			nvm_is_otp ? "OTP" : "EEPROM", gp);
155		return -ENOENT;
156	}
157}
158
159/******************************************************************************
160 *
161 * OTP related functions
162 *
163******************************************************************************/
164
165static void iwl_set_otp_access_absolute(struct iwl_trans *trans)
166{
167	iwl_read32(trans, CSR_OTP_GP_REG);
168
169	iwl_clear_bit(trans, CSR_OTP_GP_REG,
170		      CSR_OTP_GP_REG_OTP_ACCESS_MODE);
171}
172
173static int iwl_nvm_is_otp(struct iwl_trans *trans)
174{
175	u32 otpgp;
176
177	/* OTP only valid for CP/PP and after */
178	switch (trans->hw_rev & CSR_HW_REV_TYPE_MSK) {
179	case CSR_HW_REV_TYPE_NONE:
180		IWL_ERR(trans, "Unknown hardware type\n");
181		return -EIO;
182	case CSR_HW_REV_TYPE_5300:
183	case CSR_HW_REV_TYPE_5350:
184	case CSR_HW_REV_TYPE_5100:
185	case CSR_HW_REV_TYPE_5150:
186		return 0;
187	default:
188		otpgp = iwl_read32(trans, CSR_OTP_GP_REG);
189		if (otpgp & CSR_OTP_GP_REG_DEVICE_SELECT)
190			return 1;
191		return 0;
192	}
193}
194
195static int iwl_init_otp_access(struct iwl_trans *trans)
196{
197	int ret;
198
199	/* Enable 40MHz radio clock */
200	iwl_write32(trans, CSR_GP_CNTRL,
201		    iwl_read32(trans, CSR_GP_CNTRL) |
202		    CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
203
204	/* wait for clock to be ready */
205	ret = iwl_poll_bit(trans, CSR_GP_CNTRL,
206			   CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
207			   CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
208			   25000);
209	if (ret < 0) {
210		IWL_ERR(trans, "Time out access OTP\n");
211	} else {
212		iwl_set_bits_prph(trans, APMG_PS_CTRL_REG,
213				  APMG_PS_CTRL_VAL_RESET_REQ);
214		udelay(5);
215		iwl_clear_bits_prph(trans, APMG_PS_CTRL_REG,
216				    APMG_PS_CTRL_VAL_RESET_REQ);
217
218		/*
219		 * CSR auto clock gate disable bit -
220		 * this is only applicable for HW with OTP shadow RAM
221		 */
222		if (trans->cfg->base_params->shadow_ram_support)
223			iwl_set_bit(trans, CSR_DBG_LINK_PWR_MGMT_REG,
224				    CSR_RESET_LINK_PWR_MGMT_DISABLED);
225	}
226	return ret;
227}
228
229static int iwl_read_otp_word(struct iwl_trans *trans, u16 addr,
230			     __le16 *eeprom_data)
231{
232	int ret = 0;
233	u32 r;
234	u32 otpgp;
235
236	iwl_write32(trans, CSR_EEPROM_REG,
237		    CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
238	ret = iwl_poll_bit(trans, CSR_EEPROM_REG,
239				 CSR_EEPROM_REG_READ_VALID_MSK,
240				 CSR_EEPROM_REG_READ_VALID_MSK,
241				 IWL_EEPROM_ACCESS_TIMEOUT);
242	if (ret < 0) {
243		IWL_ERR(trans, "Time out reading OTP[%d]\n", addr);
244		return ret;
245	}
246	r = iwl_read32(trans, CSR_EEPROM_REG);
247	/* check for ECC errors: */
248	otpgp = iwl_read32(trans, CSR_OTP_GP_REG);
249	if (otpgp & CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK) {
250		/* stop in this case */
251		/* set the uncorrectable OTP ECC bit for acknowledgment */
252		iwl_set_bit(trans, CSR_OTP_GP_REG,
253			    CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
254		IWL_ERR(trans, "Uncorrectable OTP ECC error, abort OTP read\n");
255		return -EINVAL;
256	}
257	if (otpgp & CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK) {
258		/* continue in this case */
259		/* set the correctable OTP ECC bit for acknowledgment */
260		iwl_set_bit(trans, CSR_OTP_GP_REG,
261			    CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK);
262		IWL_ERR(trans, "Correctable OTP ECC error, continue read\n");
263	}
264	*eeprom_data = cpu_to_le16(r >> 16);
265	return 0;
266}
267
268/*
269 * iwl_is_otp_empty: check for empty OTP
270 */
271static bool iwl_is_otp_empty(struct iwl_trans *trans)
272{
273	u16 next_link_addr = 0;
274	__le16 link_value;
275	bool is_empty = false;
276
277	/* locate the beginning of OTP link list */
278	if (!iwl_read_otp_word(trans, next_link_addr, &link_value)) {
279		if (!link_value) {
280			IWL_ERR(trans, "OTP is empty\n");
281			is_empty = true;
282		}
283	} else {
284		IWL_ERR(trans, "Unable to read first block of OTP list.\n");
285		is_empty = true;
286	}
287
288	return is_empty;
289}
290
291
292/*
293 * iwl_find_otp_image: find EEPROM image in OTP
294 *   finding the OTP block that contains the EEPROM image.
295 *   the last valid block on the link list (the block _before_ the last block)
296 *   is the block we should read and used to configure the device.
297 *   If all the available OTP blocks are full, the last block will be the block
298 *   we should read and used to configure the device.
299 *   only perform this operation if shadow RAM is disabled
300 */
301static int iwl_find_otp_image(struct iwl_trans *trans,
302					u16 *validblockaddr)
303{
304	u16 next_link_addr = 0, valid_addr;
305	__le16 link_value = 0;
306	int usedblocks = 0;
307
308	/* set addressing mode to absolute to traverse the link list */
309	iwl_set_otp_access_absolute(trans);
310
311	/* checking for empty OTP or error */
312	if (iwl_is_otp_empty(trans))
313		return -EINVAL;
314
315	/*
316	 * start traverse link list
317	 * until reach the max number of OTP blocks
318	 * different devices have different number of OTP blocks
319	 */
320	do {
321		/* save current valid block address
322		 * check for more block on the link list
323		 */
324		valid_addr = next_link_addr;
325		next_link_addr = le16_to_cpu(link_value) * sizeof(u16);
326		IWL_DEBUG_EEPROM(trans->dev, "OTP blocks %d addr 0x%x\n",
327				 usedblocks, next_link_addr);
328		if (iwl_read_otp_word(trans, next_link_addr, &link_value))
329			return -EINVAL;
330		if (!link_value) {
331			/*
332			 * reach the end of link list, return success and
333			 * set address point to the starting address
334			 * of the image
335			 */
336			*validblockaddr = valid_addr;
337			/* skip first 2 bytes (link list pointer) */
338			*validblockaddr += 2;
339			return 0;
340		}
341		/* more in the link list, continue */
342		usedblocks++;
343	} while (usedblocks <= trans->cfg->base_params->max_ll_items);
344
345	/* OTP has no valid blocks */
346	IWL_DEBUG_EEPROM(trans->dev, "OTP has no valid blocks\n");
347	return -EINVAL;
348}
349
350/**
351 * iwl_read_eeprom - read EEPROM contents
352 *
353 * Load the EEPROM contents from adapter and return it
354 * and its size.
355 *
356 * NOTE:  This routine uses the non-debug IO access functions.
357 */
358int iwl_read_eeprom(struct iwl_trans *trans, u8 **eeprom, size_t *eeprom_size)
359{
360	__le16 *e;
361	u32 gp = iwl_read32(trans, CSR_EEPROM_GP);
362	int sz;
363	int ret;
364	u16 addr;
365	u16 validblockaddr = 0;
366	u16 cache_addr = 0;
367	int nvm_is_otp;
368
369	if (!eeprom || !eeprom_size)
370		return -EINVAL;
371
372	nvm_is_otp = iwl_nvm_is_otp(trans);
373	if (nvm_is_otp < 0)
374		return nvm_is_otp;
375
376	sz = trans->cfg->base_params->eeprom_size;
377	IWL_DEBUG_EEPROM(trans->dev, "NVM size = %d\n", sz);
378
379	e = kmalloc(sz, GFP_KERNEL);
380	if (!e)
381		return -ENOMEM;
382
383	ret = iwl_eeprom_verify_signature(trans, nvm_is_otp);
384	if (ret < 0) {
385		IWL_ERR(trans, "EEPROM not found, EEPROM_GP=0x%08x\n", gp);
386		goto err_free;
387	}
388
389	/* Make sure driver (instead of uCode) is allowed to read EEPROM */
390	ret = iwl_eeprom_acquire_semaphore(trans);
391	if (ret < 0) {
392		IWL_ERR(trans, "Failed to acquire EEPROM semaphore.\n");
393		goto err_free;
394	}
395
396	if (nvm_is_otp) {
397		ret = iwl_init_otp_access(trans);
398		if (ret) {
399			IWL_ERR(trans, "Failed to initialize OTP access.\n");
400			goto err_unlock;
401		}
402
403		iwl_write32(trans, CSR_EEPROM_GP,
404			    iwl_read32(trans, CSR_EEPROM_GP) &
405			    ~CSR_EEPROM_GP_IF_OWNER_MSK);
406
407		iwl_set_bit(trans, CSR_OTP_GP_REG,
408			    CSR_OTP_GP_REG_ECC_CORR_STATUS_MSK |
409			    CSR_OTP_GP_REG_ECC_UNCORR_STATUS_MSK);
410		/* traversing the linked list if no shadow ram supported */
411		if (!trans->cfg->base_params->shadow_ram_support) {
412			ret = iwl_find_otp_image(trans, &validblockaddr);
413			if (ret)
414				goto err_unlock;
415		}
416		for (addr = validblockaddr; addr < validblockaddr + sz;
417		     addr += sizeof(u16)) {
418			__le16 eeprom_data;
419
420			ret = iwl_read_otp_word(trans, addr, &eeprom_data);
421			if (ret)
422				goto err_unlock;
423			e[cache_addr / 2] = eeprom_data;
424			cache_addr += sizeof(u16);
425		}
426	} else {
427		/* eeprom is an array of 16bit values */
428		for (addr = 0; addr < sz; addr += sizeof(u16)) {
429			u32 r;
430
431			iwl_write32(trans, CSR_EEPROM_REG,
432				    CSR_EEPROM_REG_MSK_ADDR & (addr << 1));
433
434			ret = iwl_poll_bit(trans, CSR_EEPROM_REG,
435					   CSR_EEPROM_REG_READ_VALID_MSK,
436					   CSR_EEPROM_REG_READ_VALID_MSK,
437					   IWL_EEPROM_ACCESS_TIMEOUT);
438			if (ret < 0) {
439				IWL_ERR(trans,
440					"Time out reading EEPROM[%d]\n", addr);
441				goto err_unlock;
442			}
443			r = iwl_read32(trans, CSR_EEPROM_REG);
444			e[addr / 2] = cpu_to_le16(r >> 16);
445		}
446	}
447
448	IWL_DEBUG_EEPROM(trans->dev, "NVM Type: %s\n",
449			 nvm_is_otp ? "OTP" : "EEPROM");
450
451	iwl_eeprom_release_semaphore(trans);
452
453	*eeprom_size = sz;
454	*eeprom = (u8 *)e;
455	return 0;
456
457 err_unlock:
458	iwl_eeprom_release_semaphore(trans);
459 err_free:
460	kfree(e);
461
462	return ret;
463}
464IWL_EXPORT_SYMBOL(iwl_read_eeprom);